All wages were earned and reported in IL by Employer

The employee was a resident of Alabama for  3 months and the other 9 months was a resident of Illinois

I input all wages to IL according to W2.

But what should I do with these 3 mounts living in AL? I think I should report some wages there too. I calculated it separately from Payroll. And I think they have to be reported in AL Sch W-2 column J (additional income from other States)

And my question was how to do this.